Athena's extensive experience gained in supplying the most prestigious O.E.M. motorcycle manufacturers has brought to their R&D technicians the skills necessary to make their exclusive high-quality components. Athena forged pistons offer the best solution in terms of performance, cost and reliability. Compared to cast pistons, Forged pistons are tougher and more durable than cast pistons, and will stand up to the abuse of todays high performance motorcycles. Forged piston kits are made to OEM stock specifications and include piston, rings and wrist pin. Compression Ratio 14.1:1 Fitment: Honda CRF250 20-23 D.79mm OEM Replacement